Many sub-modules in the area of driver assistance systems, whether they are based on radar or cameras, have a certain chance of failure. In order to use their output signals in a vehicle wide system it is important to receive some sort of quality estimate in addition to the signal. This quality estimate should give the information if the signal is correct and within a certain accuracy bandwidth or not. Especially module estimating the ego-motion from a sensor like a monocular camera requires this important information.
The output of such a module is often used for applications like camera calibration or serves as an ego-motion input for the object trackers, e.g., for lane marking, vehicle and pedestrian trackers. In these applications a false input can lead to a false and crucial system reaction. The additional information for the signal quality is often termed as confidence.